Welcome to Healing Well! Sorry to hear you're having difficulties with GERD, but glad to hear the worst is over. If you were 305, you were likely eating a lot of food. When you have stomach issues that keep you from eating as much, then you won't be able to maintain the same weight. Also, when you stop eating and are not keeping food down, you're losing some muscle as well.
If you want to gain weight (lucky you...most want the opposite), then you'll need to eat many smaller meals. Your stomach won't accept the large amounts you were used to eating, as it sounds like it is still not feeling perfect.
Glad you joined the forum!
Nissen Fundoplication 2/09
"Whatever you fight, you strengthen, and what you resist, persists.”
“Worry pretends to be necessary but serves no useful purpose”
“Accept - then act. Whatever the present moment contains, accept it as if you had chosen it. Always work with it, not against it.”